Intel Yorkfield is a Ray-Trace monster
 

The reason for this is because of the advances made by the RT group inside Intel. Daniel Pohl, author of Quake III and IV Ray-Trace demonstrations held a presentation that showed that Ray-Trace came from 4FPS in 640x480 resolution on a 50 Xeon CPUs machine to over 90 FPS (frames per second) in 768x768 on a single machine with Yorkfield processor running at sub-3GHz clockspeed.

http://www.theinquirer.net/default.aspx?article=41858

Ray Tracing game engine would be most realistic looking ever, and make games completely CPU dependent ;)